Bridges are everywhere. From small rural overpasses to massive spans crossing rivers and valleys, these structures keep people and goods moving. But they don’t last forever without regular maintenance and inspection. That’s where certified bridge inspectors like Corey Work come in. In a recent conversation on The Propaganda Construction Show, Corey broke down what goes into inspecting a bridge, how often it happens, and what inspectors are looking for.
How Often Do Bridges Get Inspected?
Bridge inspections follow a routine schedule, usually every 24 months. However, some bridges require more frequent checks based on their condition. If a bridge shows significant issues—like structural concerns or erosion—it can be put on a cursory schedule, meaning it gets inspected every 12, 6, or even 3 months. While 3-month inspections are rare, they do happen, usually after an event like a barge collision or severe flooding.
The Three Main Components of a Bridge
When bridge inspectors head out, they aren’t just giving bridges a quick once-over. They check three major structural components:
- Deck – This is the surface you drive on, including pavement, railings, and expansion joints.
- Superstructure – The support system under the deck, including beams and girders.
- Substructure – The foundation elements, such as abutments (the supports at each end of the bridge) and piers (supports under the span).
Every bridge has these same basic components, and inspectors evaluate each one for wear, damage, or movement.
What Are Inspectors Looking For?
Each inspection follows a standard checklist, but certain bridges may have unique concerns. For example, a bridge in a flood-prone area might require extra attention to scour—the erosion of soil and material around its supports. If water washes away too much sediment, the bridge’s foundation can weaken, leading to serious problems.
Another issue is undermining, where erosion occurs directly beneath a bridge footing. If an inspector can slide a rod underneath a support, that’s a major red flag. Drift, or debris buildup (such as logs and branches), can also be a problem if it puts pressure on bridge piers.
Then there’s the concrete itself. Concrete cracks—it’s just a fact. Inspectors monitor these cracks over time, measuring their size and rate of progression. If they get too large, it’s time for repairs, usually with crack sealers or patches. But as Corey pointed out, these fixes don’t last forever. Some cracks will need more significant repairs over time.
For steel bridges, inspectors check for corrosion and section loss. If rust eats away at too much of an I-beam’s flange or web, it compromises the bridge’s strength. Proper maintenance involves not just painting over rust but cleaning the surface first to prevent future deterioration.
Bridges Move—And That’s Normal
One thing most people don’t realize? Bridges move. They aren’t rigid structures; they expand and contract with temperature changes and shift slightly under heavy loads. That’s why bridges have expansion joints—so they can flex without breaking.
Ever been stuck in traffic on a bridge and felt it swaying? That’s by design. It might make your stomach drop, but without that flexibility, the structure would be more likely to fail under stress.
The Bottom Line
Bridge inspections are critical to keeping roads safe. Inspectors like Corey Work check for everything from cracks and corrosion to scour and debris buildup. Some issues require immediate repairs, while others get monitored over time. Either way, regular inspections ensure that bridges stay standing, even when loaded down with semi-trucks and rush hour traffic.
So, the next time you’re crossing a bridge and feel it move a little, don’t panic—it’s probably just doing its job. But rest assured, there’s a team of professionals out there keeping an eye on it, just in case.